Agree with you, but one of the things holding back a fundamental shift in the design philosophy of forum user interfaces is that the people who still use forums like the way they are organized and the way they work. They don't all like the casual Facebook user interface. So to move away from the format that is embraced by the people who still use forums, in hopes to attract those who have moved away from forums is a bit risky.
With that said, it seems safe to say that the reason people have embraced Fecalbook, I mean Facebook, is due to the ease of use - mainly on mobile devices. Offering options that blend in user interface elements that are widely used on social media mobile apps makes a LOT of sense. Give the options toggles to be disabled completely, and allow them to be turned on in different ways. Giving admins the ability to make the interface easier to engage with, and slowly turn the forum into a more modern looking system in ways that people have gotten used to with the popular social platforms makes sense. Giving the user the power to adjust the way they browse the forum and how it looks is also a good idea to counteract the negative response to change from the existing user base.
I see members in the automotive community saying "make forums great again" on FB quite a bit (and not to be political). Many people on there truly do want to see forums make a big comeback, because forums do have a way of generating some great content from members in a way that social media doesn't. And some of us want to be the ones to help make that happen. I know I do. We don't want to see forums turn into data archives where people only go to search for info, just to hop back to their FB app to participate.
I think making more content available in more places to be engaged with, as suggested here, is a good step in the right direction. Adding snippets of the thread content in several places where there are only thread titles makes a lot of sense. Allowing them to view a few replies makes sense. Allowing them to post reactions to the thread and the replies (likes) at that point makes sense. A "read more" link to draw them into the thread to read the replies before they post their own makes sense.
Unfortunately, FB has perpetuated the behavior of posting before you read what others before you posted - both for the initial post and the replies to posts. You know it's bad when repetitive questions and answers on FB actually make forums look good. So there has to be some careful thought put into how to show them more content while pushing them to read what others have said before they post themselves.
